Herein, we report a Nb/ZnO nanocatalyst for the efficient conversion of levulinic acid, a platform molecule easily obtained from lignocellulosic biomass, to N-heterocycles under mild reaction conditions and the absence of solvent. Nb/ZnO nanocatalysts were synthesized by a mechanochemical-assisted and sacrificial template method, involving orange peel valorization toward nanostructured materials. Two different synthetic approaches, either one-step or two-step, as well as the amount of niobium deposited onto the ZnO support were investigated in order to obtain the nanocatalyst with the optimal catalytic properties. Results revealed the critical role of the niobium for LA conversion. The nanocatalyst containing 10 wt% of niobium and prepared following a two-step approach (10 %Nb/ZnO_2) exhibited the best catalytic performance with a 94.5% of conversion and 97.4% of selectivity towards one specific N-heterocycle compound. This work exemplifies the possibility of sustainable production of value-added compounds, in particular N-heterocycles, from biomass-derived feedstocks by playing with the design of improved catalysts. Importantly, this research area provides sustainable alternatives to the current chemical industry that is heavily dependent on fossil fuels.

在此，我们报道了一种Nb / ZnO纳米催化剂，用于将乙酰丙酸（一种从木质纤维素生物质容易获得的平台分子）有效转化为N-杂环在温和的反应条件下和没有溶剂的情况下。通过机械化学辅助和牺牲模板法合成了Nb / ZnO纳米催化剂，该方法涉及橙皮对纳米结构材料的增值。为了获得具有最佳催化性能的纳米催化剂，研究了两种不同的合成方法（一步法或两步法）以及沉积在ZnO载体上的铌的量。结果揭示了铌对洛杉矶转化的关键作用。按照两步法制备的含铌10％（重量）的纳米催化剂（10％Nb / ZnO_2）表现出最佳的催化性能，其转化率为94.5％，对一种特定N的选择性为97.4％。-杂环化合物。这项工作例证了通过改进催化剂的设计，可以从生物质衍生的原料中可持续生产增值化合物，特别是N-杂环的可能性。重要的是，该研究领域为当前严重依赖化石燃料的化学工业提供了可持续的替代方案。